1. Field of the Invention
This invention relates to an encoder for detecting a rotational position, etc., of a rotor of an NC machine tool and the like, in particular a magnetic encoder for detecting changes in a magnetic flux in response to rotational movement of a rotor to obtain a rotational position, etc., of the rotor.
2. Description of the Related Art
A magnetic encoder is used in a machine tool, for example, for measuring a rotational velocity or a rotational position, etc., of a rotor, based on a magnetic flux which changes in response to rotational movement of the rotor (see JP 2000-292507 A).
There is a need for a magnetic encoder having a thin detection surface in order to improve sensitivity of a magnetic sensor.